Origin of the Bohai Sea Basin, North China Craton, and implications for bidirectional back-arc extension in the East Asian continental margin

<p>The Bohai Sea Basin in eastern China is located in a back-arc extensional regime due to northwestward subduction of the Philippine Sea Plate and westward subduction of the Pacific Plate underneath the Eurasian Plate. The Bohai Sea Basin and surrounding region experience frequent earthquakes...

Full description

Saved in:
Bibliographic Details
Main Authors: A. L. Chen, X. Chen
Format: Article
Language:English
Published: Copernicus Publications 2025-01-01
Series:Solid Earth
Online Access:https://se.copernicus.org/articles/16/63/2025/se-16-63-2025.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832590733827112960
author A. L. Chen
X. Chen
author_facet A. L. Chen
X. Chen
author_sort A. L. Chen
collection DOAJ
description <p>The Bohai Sea Basin in eastern China is located in a back-arc extensional regime due to northwestward subduction of the Philippine Sea Plate and westward subduction of the Pacific Plate underneath the Eurasian Plate. The Bohai Sea Basin and surrounding region experience frequent earthquakes. Previous recognition of the origin of the Bohai Sea Basin was limited by the understanding of the back-arc extensional mode perpendicular to the subduction zone in the eastern Asian continental margin. In this paper, a new model for the genesis of the Bohai Sea Basin is proposed based on the construction of a major fault system and investigation of several main boundaries enclosing the Bohai Sea Basin. We have made field investigations and analyses of tectonic landforms and boundary faults on the northwest coast of the Bohai Sea and eastern and western margins of the Liaodong Peninsula, which revealed left-lateral strike-slip faults along the northwest coast of the Liaodong Bay and western margin of the Liaodong Peninsula. Then, we conducted a geological comparison of the Liaodong and Jiaodong Blocks and surrounding areas, as well as a structural interpretation of an aeromagnetic anomaly map of this region. We propose a right-lateral strike-slip fault between the eastern margin of the Liaodong Block and northwestern margin of the Jiaodong Block. This mode of movement may have resulted from the NE stretching, which is parallel to the subduction zone in the northwestern Pacific margin. Therefore, we suggest that the formation of the Bohai Sea Basin resulted from trench-parallel and trench-perpendicular extension. We speculate that the two-direction extension perpendicular and parallel to the subduction zone should be the basic pattern of the back-arc extension with a spherical geometric effect.</p>
format Article
id doaj-art-325dbbe397e14598be05005fc555e4e3
institution Kabale University
issn 1869-9510
1869-9529
language English
publishDate 2025-01-01
publisher Copernicus Publications
record_format Article
series Solid Earth
spelling doaj-art-325dbbe397e14598be05005fc555e4e32025-01-23T08:08:13ZengCopernicus PublicationsSolid Earth1869-95101869-95292025-01-0116638010.5194/se-16-63-2025Origin of the Bohai Sea Basin, North China Craton, and implications for bidirectional back-arc extension in the East Asian continental marginA. L. Chen0X. Chen1Northview High School, Johns Creek, GA 30097, USASinoProbe Laboratory, Chinese Academy of Geological Sciences, Beijing 100037, China<p>The Bohai Sea Basin in eastern China is located in a back-arc extensional regime due to northwestward subduction of the Philippine Sea Plate and westward subduction of the Pacific Plate underneath the Eurasian Plate. The Bohai Sea Basin and surrounding region experience frequent earthquakes. Previous recognition of the origin of the Bohai Sea Basin was limited by the understanding of the back-arc extensional mode perpendicular to the subduction zone in the eastern Asian continental margin. In this paper, a new model for the genesis of the Bohai Sea Basin is proposed based on the construction of a major fault system and investigation of several main boundaries enclosing the Bohai Sea Basin. We have made field investigations and analyses of tectonic landforms and boundary faults on the northwest coast of the Bohai Sea and eastern and western margins of the Liaodong Peninsula, which revealed left-lateral strike-slip faults along the northwest coast of the Liaodong Bay and western margin of the Liaodong Peninsula. Then, we conducted a geological comparison of the Liaodong and Jiaodong Blocks and surrounding areas, as well as a structural interpretation of an aeromagnetic anomaly map of this region. We propose a right-lateral strike-slip fault between the eastern margin of the Liaodong Block and northwestern margin of the Jiaodong Block. This mode of movement may have resulted from the NE stretching, which is parallel to the subduction zone in the northwestern Pacific margin. Therefore, we suggest that the formation of the Bohai Sea Basin resulted from trench-parallel and trench-perpendicular extension. We speculate that the two-direction extension perpendicular and parallel to the subduction zone should be the basic pattern of the back-arc extension with a spherical geometric effect.</p>https://se.copernicus.org/articles/16/63/2025/se-16-63-2025.pdf
spellingShingle A. L. Chen
X. Chen
Origin of the Bohai Sea Basin, North China Craton, and implications for bidirectional back-arc extension in the East Asian continental margin
Solid Earth
title Origin of the Bohai Sea Basin, North China Craton, and implications for bidirectional back-arc extension in the East Asian continental margin
title_full Origin of the Bohai Sea Basin, North China Craton, and implications for bidirectional back-arc extension in the East Asian continental margin
title_fullStr Origin of the Bohai Sea Basin, North China Craton, and implications for bidirectional back-arc extension in the East Asian continental margin
title_full_unstemmed Origin of the Bohai Sea Basin, North China Craton, and implications for bidirectional back-arc extension in the East Asian continental margin
title_short Origin of the Bohai Sea Basin, North China Craton, and implications for bidirectional back-arc extension in the East Asian continental margin
title_sort origin of the bohai sea basin north china craton and implications for bidirectional back arc extension in the east asian continental margin
url https://se.copernicus.org/articles/16/63/2025/se-16-63-2025.pdf
work_keys_str_mv AT alchen originofthebohaiseabasinnorthchinacratonandimplicationsforbidirectionalbackarcextensionintheeastasiancontinentalmargin
AT xchen originofthebohaiseabasinnorthchinacratonandimplicationsforbidirectionalbackarcextensionintheeastasiancontinentalmargin